Firmware Builders for nodewatcher
This repository contains OpenWrt based firmware builders for building default nodewatcher firmware images. We use this firmware in the wlan slovenija network and you can use it directly or use it as a base for your own firmware. To ease deployment, the builders are provided as a set of Docker images.
Pre-built images are available on the public Docker Hub:
- wlanslovenija/firmware-base (base image for all builders)
- wlanslovenija/openwrt-imagebuilder-base (base image for OpenWrt builders)
- wlanslovenija/openwrt-builder (actual OpenWrt builders)
Most of the changes to the stock OpenWrt firmware we do are available through opkg packages.
When nodewatcher is generating firmware images, it specifies the profile, packages, and configuration files automatically. The commands described below are used only when developing, testing, or using firmware builders without nodewatcher.
In order to run the Dockerized builder, for example
one simply needs to do the following:
$ docker run --detach=true --name builder-openwrt-18.06.0_ar71xx_generic \ --env "BUILDER_PUBLIC_KEY=ssh-rsa AAAA...2n builder@host" \ wlanslovenija/openwrt-builder:18.06.0_ar71xx_generic
BUILDER_PUBLIC_KEY environmental variable is used to specify the public key that will be
accepted for SSH authentication. In case one uses nodewatcher, the corresponding private key needs
to be configured in its builder configuration.
We pre-build and publish
wlanslovenija/openwrt-builder images with multiple tags for different versions and platforms.
Tag is in the format
<OpenWrt release>_<target>_<subtarget>. For example,
corresponds to the firmware at tag 18.06.0 of OpenWrt repository, for the OpenWrt 18.06.0 release,
ar71xx target and
One running, you san SSH into the builder using the private keys which corresponds to the
Alternatively, you can use Docker to connect to the running builder container locally:
docker exec -t -i builder-openwrt-18.06.0_ar71xx_generic bash
Once you are in, you can build the image you are interested in. For example:
cd /builder/imagebuilder su builder make image PROFILE="TLWR1043" PACKAGES="wireless-tools wpad-mini kmod-netem kmod-pktgen ntpclient qos-scripts iperf horst wireless-info cronscripts iwinfo nodewatcher-agent nodewatcher-agent-mod-general nodewatcher-agent-mod-resources nodewatcher-agent-mod-interfaces nodewatcher-agent-mod-wireless nodewatcher-agent-mod-keys_ssh nodewatcher-agent-mod-clients uhttpd ip-full"
You can use only packages which were made when creating this builder (are listed in the
You cannot compile custom packages at this step anymore.
If you need additional packages, you have to modify the firmware builders.
Resulting image will be in
Accessing Built Images
You can use
scp to copy the image out. Alternatively, you can use Docker:
docker cp builder-openwrt-18.06.0_ar71xx_generic:/builder/imagebuilder/bin/ar71xx/generic/openwrt-ar71xx-generic-tl-wr1043nd-v1-squashfs-factory.bin .
Modifying Firmware Builders
If you want to modify firmware builders to generate somehow different OpenWrt firmware, you should first make sure that firmware image works for you when it is generated directly through normal OpenWrt firmware building process. Firmware builders are not suitable environment for development of OpenWrt firmware itself. Once you have a working firmware image you want you can proceed with modifying firmware builders to build this new firmware for you. Instead of using pre-built Docker images from Docker Hub you will now have to build Docker images for new firmware builders yourself.
OpenWRt firmware builders are defined through configuration files found under
packagescontains a list of WlanSlovenija custom packages that Nodewatcher uses and that will be compiled.
Each branch definition is in the format
OpenWrt_Release:OpenWrt_Target:OpenWrt_SubTargetwhere fields are as follows:
OpenWrt_Releaseis a OpenWrt release version (eg.
18.06.0for stable or
OpenWrt_Targetis a OpenWrt target relative to OpenWrt downloads (eg.
OpenWrt_SubTargetis a OpenWrt subtarget to OpenWrt downloads (eg.
Relationships of the various Dockerfiles are explained in Build System Internals.
The next step is to build the correct
wlanslovenija/openwrt-builder image. There is a script that makes this
easier, so you can run:
sudo ./openwrt/scripts/build <OpenWrt_Release> <OpenWrt_Target> <OpenWrt_SubTarget>
For example, to build for the 18.06.0 release for the ar71xx target and generic subtarget, run:
sudo ./openwrt/scripts/build 18.06.0 ar71xx generic
After the build completes successfully,then, a Docker image named
wlanslovenija/openwrt-builder:18.06.0_ar71xx_generic will be available.
You can now run and use the new image in the same way as pre-built images. You can use them directly, or through nodewatcher. If you are adding support for a new device, you have add to nodewatcher also a new device descriptor. Add it to your local instance of nodewatcher and test it by generating an image through nodewatcher for this new device, flashing it, and testing it, to make sure everything works as intended. If it does, then contribute both changes to this repository and your new device descriptor back so that it is available to others as well.
Cloud Builder API
The following is the Cloud Builder API 0.1 standard. We are proposing it to facilitate easy sharing, reuse, and swapping of builders and testing out of new firmwares in the wider community.
- There is a system user
builderunder which you should be running the build.
- OpenWrt image builder systems are available under
To facilitate the cloud use of builders the following is optional, but recommended.
- OpenWrt packages are available through the builder over HTTP with feeds directly under the HTTP root so
packagesfeed is available under
- A metadata file served over HTTP at
/metadata, encoded as a JSON object with the following fields:
platformwhich should be
architecturewhich should contain the name of the architecture the builder is for (for example
versionwhich should contain a string identifying the version of the builder (for example
packageswhich should contain an object describing included package information. Keys should be package names and each package is represented by an object with the following fields:
- Support for SSH access using the
BUILDER_PUBLIC_KEYto authenticate the client connection.
Build System Internals
The build system is composed from multiple Docker images. Some of them are hardcoded and the others are
generated using scripts. While currently only the OpenWrt platform is supported, the build system is
designed so it could support others as well. For example, OpenWrt-specific build configuration is under
example the file
openwrt/packages specifies which packages get compiled.
The docker images for the build process are the following:
firmware-base(the top-level Dockerfile) prepares a minimal environment with required dependencies to build stuff.
docker/runtime) prepares a minimal environment used to run (not build) the final OpenWrt image builder images. It sets up an HTTP and SSH servers that are used by nodewatcher to connect to the container and build the images. The HTTP server is also used to serve the built OPKG packages.
These two are the only Dockerfiles that are hardcoded, all the others are generated by the above scripts and
the generated files are stored in the
docker/openwrt subdirectory. Calling
overwrite anything in this directory, so it shouldn't be edited by hand.
For OpenWrt, the following Docker images are used:
firmware-baseand comes in multiple tags (one for each OpenWrt branch we support, currently these are Barrier Breaker and Chaos Calmer). This image contains a complete OpenWrt buildsystem, prepared for building our firmware (we configure some special feeds and apply some atches). The image does not build anything, it just prepares it so that further stages can use it.
openwrt-buildsystemand comes in multiple tags (one for each combination of OpenWrt branch and architecture that we support). This image is internal and is not published in the Docker hub as it would be too big (it contains the complete built OpenWrt toolchain). The stage 1 builder uses the prepared buildsystem to build the OpenWrt image builders.
firmware-runtimeand is generated from the respective
docker-build-buildersscript. It also comes in multiple tags, one for each combination of firmware version, OpenWrt branch and architecture that we support. This Docker image contains the OpenWrt image builder that can be used to quickly generate firmware images without needing to compile anything.
Source Code, Issue Tracker and Mailing List
For development wlan slovenija open wireless network development Trac is used, so you can see existing open tickets or open a new one there. Source code is available on GitHub. If you have any questions or if you want to discuss the project, use development mailing list.